GEM E4 Batteries show charged but car slowly dies after 100 yard

GEM 2008 E4

Batteries show fully charged on Dashboard and using a volt meter on each battery shows each on ~13V when tested. Batteries are about 2 years old.

Symptom: It will start out and run up to only about 15 mph and start to die to a dead stop. I have set on charge the entire night with same result.

There are no error codes. Other threads mention, possible issues, of the throttle assembly, controller or motor.
If you have experienced this in the past and know where to look, I would appreciate any help.


Are they still at 13v when you come back?

Yes. They still show fully charged.

The puzzling thing is that I keep the car plugged in and we use it regularly. It was running fine one day then the next day this occurred. There was no degradation of batteries appearing to get weaker it just dropped off, which leads me to believe it may be something else.

Check battery connections. A bad one will get warm after driving.
You can also check the whole string with a meter. See if voltage drops under load.

It appears you have a bad battery/s in the pack. Do a “Brake Load” test on each battery. The dud will show up

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How do I “Brake Load” test? Batteries all fully charged, I went about 100 ft it died and reread every battery individually. They all started around 12.5V and tested like 12.4V after it died.

Could you please explain what a brake load test is? Thanks for your help.

He means test voltage under load. Butt up against something and measure while applying a little throttle.
A bad battery or connection will drop.

Got it. I will try that. Thanks.

You can buy 12v battery load testers for pretty cheep $20. You hook it up and flick a switch and it places a load on the battery and it will tell you the battery’s strength.

A bad battery can fool you with fake voltage. Example it will show you 12.8 volts but as soon as you place a load on it, the battery will fall on its face. So don’t place all your faith in the Volt meter. It’s only 1 indication of a Battery’s health.
A brand new battery should but up over 600 cold cranking amps. So if you test all your battery’s they should be up in the 600 CCA Range the one that’s low is the culprit. Good luck. Also you may want to have the battery’s refreshed or restored. Find a local guy that does battery restoration he can most of the time bring a dead battery back to life

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Thanks. I jacked it up and put it on ramps and tested all 6 under load and they all test 12.45 -12.46V under load.

Do you think I still need to test amps? Thanks.

How were you able to load the motor on ramps?
Yes, you need to test batteries under load.
Also across the whole string to look for bad connection.

I took a car jack to raise front of the GEM up and took one tire ramp (Looks like a wedge you drive your car onto, you put one under each tire of the car when you want to work under it in the driveway), and put that under the middle of the front of the GEM which kept both tires off the ground. I had someone put in forward and press the gas pedal and I tested each battery individually while the front tires were moving.

Does that not work for getting a true “Load reading”? I have not done this before so I am using dumb logic on what a Load test means. Any help is appreciated. Thanks.

You need to draw 150-200 amps to get a good test. More is better.
Spinning the wheels won’t put much of a load on them.
A load tester does the same and reads the amps. As Grant suggested.

Thanks. I guess I am off to the store tomorrow to buy a load tester. I appreciate the help. I will post my results. Thanks.

OK. I bought a 12 V battery load tester. I tested all batteries individually under load and they show as fine. Is it possible there is an issue with my controller or engine? Thanks.

Put your volt meter on 1 battery hold your foot on the brake HARD and push the throttle for 2 seconds and note the voltage. Do all 6 batteries. The dud will show up.


I have this same issue. I have taken the individual batteries to a battery store for testing. All test within specs. I have been recently wondering if it could be the accelerator assembly.

What does it do after 100 yards and what happens when you let off the throttle pedal completely and then push on it again?

Another thing to do is remove the dashboard, clip a volt meter across the speed controller inputs and drive while watching your volt meter. Does the voltage quickly sag or stay at full voltage? Do you hear a click when it stops after 100 yards?


If your cart only goes a short distance and dies and the battery pack is charged. Suspect the Throttle assembly.

NOTE The throttle unit is uber expensive. Try to borrow one and substiute to verify that this will fix the problem.

In 5 years I have experienced this once. I worked on the cart 8 hours before I determined this as the cause.